Latest Articles from Plant Ecology and Evolution Latest 55 Articles from Plant Ecology and Evolution https://plecevo.eu/ Thu, 28 Mar 2024 18:51:52 +0200 Pensoft FeedCreator https://plecevo.eu/i/logo.jpg Latest Articles from Plant Ecology and Evolution https://plecevo.eu/ Marijordaania (Celastraceae: Cassinoideae), a new monotypic genus from South Africa https://plecevo.eu/article/116544/ Plant Ecology and Evolution 157(1): 100-112

DOI: 10.5091/plecevo.116544

Authors: Abraham E. van Wyk, Richard G.C. Boon

Abstract: Background and aims – The species name Gymnosporia filiformis, validly published in a 1927 revision of South African Celastraceae, was based on syntypes representing both Maytenus cordata and a new species. Subsequent studies supported the distinction of Gymnosporia and Maytenus as separate genera. From 1984, this new species was provisionally referred to by the designation “Maytenus sp. A”. Maytenus in Africa comprises a diverse group of species not closely related to the New World members of Maytenus. Here, we clarify the taxonomic identity and generic placement of G. filiformis, and compare it with species with which it has historically been confused. Material and methods – Descriptions and observations are based on extensive field work, supported by conventional taxonomic methods, including study of relevant literature and herbarium collections. Key results – The name Gymnosporia filiformis is lectotypified using a syntype representing “Maytenus sp. A”. We describe a new monotypic genus, Marijordaania, to accommodate “Maytenus sp. A”, and propose the new combination, Marijordaania filiformis. An amended description is provided for the species. It is morphologically quite different from Maytenus cordata, but also from Maytenus acuminata and Maytenus abbottii, species with which it has been confused in the past. Marijordaania filiformis grows in the understorey of evergreen Scarp Forest and is relatively rare, known with certainty only from KwaZulu-Natal and the Eastern Cape provinces, South Africa. A preliminary conservation assessment suggests that M. filiformis should be classified as Endangered. Conclusion – Marijordaania filiformis is a taxonomically isolated species with no apparent close relatives among African Celastraceae. While the generic status of other African members of Maytenus still needs to be resolved, it would not impact the taxonomic status of Marijordaania. In a recent key for Celastraceae genera based on morphology and geography, M. filiformis ran to the genus Euonymus, but this association lacks support from available molecular evidence.

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Research Article Wed, 28 Feb 2024 09:26:00 +0200
Dispersal and persistence of cup plant seeds (Silphium perfoliatum): do they contribute to potential invasiveness? https://plecevo.eu/article/104640/ Plant Ecology and Evolution 157(1): 75-87

DOI: 10.5091/plecevo.104640

Authors: L. Marie Ende, Lukas Hummel, Marianne Lauerer

Abstract: Background and aims – The cup plant (Silphium perfoliatum) is being grown in Germany as a promising new bioenergy crop with an increasing area under cultivation in the last years. Its alien status, its high productivity, and high reproductive potential could carry the risk of this species becoming invasive. The present study investigates the dispersal and persistence of cup plant seeds, to contribute to the assessment of its invasive potential. Material and methods – For this purpose, four experimental studies were conducted in Germany, Central Europe: wind dispersal distance was measured in a field experiment for wind speeds up to 7 m.s-1. The seeds were offered to rodents in different habitats near to a cup plant field. We observed seed persistence and germination over 4 weeks storing in water and over 4 years storing in different soil depths. Key results – Cup plant seeds are dispersed by wind only over a few meters. In the forest, rodents removed 100% of the offered seeds, in open habitats none. Independent of the duration of storage in water, germination rate of the cup plant seeds was constantly high. Most of the seeds already germinated in water in the first two weeks. Stored on the soil surface and at 10 cm soil depth, the seeds germinated already in the first two years. Stored at 30 cm depth, one third of the seeds retained their germination ability over four years. Conclusion – Wind serves as short-distance dispersal vector for cup plant seeds. Rodents remove the seeds, but it is unknown whether they disperse them or just eat them. Water could disperse the seeds, which retain their germination ability, over long distances. The cup plant could therefore spread and possibly become invasive in Central Europe, and therefore measures are suggested to prevent its dispersal and spontaneous settlement.

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Research Article Wed, 14 Feb 2024 09:30:00 +0200
Floristic and structural distinctness of monodominant Gilbertiodendron dewevrei forest in the western Congo Basin https://plecevo.eu/article/111539/ Plant Ecology and Evolution 157(1): 55-74

DOI: 10.5091/plecevo.111539

Authors: Ellen Heimpel, Antje Ahrends, Kyle G. Dexter, Jefferson S. Hall, Josérald Mamboueni, Vincent P. Medjibe, David Morgan, Crickette Sanz, David J. Harris

Abstract: Background and aims – The forests of the Congo Basin contain high levels of biodiversity, and are globally important for carbon storage. In order to design effective conservation strategies, and to accurately model carbon stocks, a fine-scale understanding of the different forest types that make up this forest block is needed. Monodominant Gilbertiodendron dewevrei forest covers large areas of the Congo Basin, but it is currently unclear whether it is sufficiently distinct from adjacent mixed terre firme forest to warrant separate treatment for conservation planning and carbon calculations. This study aimed to compare the structure and diversity of monodominant and mixed forest, and ask whether there is a unique vascular plant community associated with G. dewevrei forest. Material and methods – We utilised a combination of plot data and herbarium specimens collected in the Sangha Trinational (a network of protect areas in Cameroon, Central African Republic, and the Republic of Congo). Plot inventories were used to compare G. dewevrei forest and mixed forest for stem density, basal area, above ground biomass, stem size distribution, species diversity, and species composition. In addition, a database of 3,557 herbarium specimens was used to identify species of vascular plant that are associated with G. dewevrei forest. Key results – Gilbertiodendron dewevrei forest is distinct in both structure and species composition from mixed forest. Gilbertiodendron dewevrei forest has a lower stem number (of trees ≥ 10 cm), but a greater proportion of larger trees (> 70 cm), suggesting higher carbon stocks. The species composition is distinct from mixed forest, with 56 species of vascular plant significantly associated with G. dewevrei forest. Conclusion – Monodominant G. dewevrei forest in the Sangha Trinational is both compositionally and structurally distinct from mixed forest. We therefore recommend this forest type be considered separately from mixed forest for conservation planning and carbon stock calculations.

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Research Article Wed, 7 Feb 2024 09:55:00 +0200
The evolution of paleo- and neo-endemic species of Cactaceae in the isolated Valley of Tehuacán-Cuicatlán, Mexico https://plecevo.eu/article/110352/ Plant Ecology and Evolution 157(1): 42-54

DOI: 10.5091/plecevo.110352

Authors: Fabiola Soto-Trejo, Francisco Robles, Rafael Lira, Luis A. Sánchez-González, Enrique Ortiz, Patricia Dávila

Abstract: Background and aims – Endemism may be defined according to the time of origin of taxa. Neo-endemics refer to relatively recent species that have not dispersed outside their ancestral areas. In contrast, paleo-endemics refer to species of ancient origins, which are currently geographically restricted but probably were more widespread in the past. Geographically, endemism areas may also be based on the co-occurrence of more than one species. We aimed to qualitatively identify the neo-endemism and paleo-endemism of endemic Cactaceae of the Tehuacán-Cuicatlán Valley, as well as to quantitatively assess paleo- and neo-endemics areas. Material and methods – Using a dated molecular phylogeny of endemic Cactaceae, we defined paleo- and neo-endemics using an arbitrary boundary of 2.6 million years ago; we also assessed the significance of concentrations of these species using a categorical analysis of paleo- and neo-endemism. Key results – Our results showed that most endemic Cactaceae in the Tehuacán-Cuicatlán Valley arose throughout the Pleistocene, while categorical analysis indicated localised mixed- and super-endemism (including both paleo- and neo-endemics) areas. Conclusion – We suggest that paleo- and neo-endemics, as well as localised mixed-endemism areas, may have originated due to a probable high climatic stability in the Tehuacán-Cuicatlán Valley, which in addition to topographically rugged and ecologically complex zones (e.g. ecotones, isolated habitat patches) may have allowed it to function as a refuge throughout Pleistocene climatic changes, mainly promoting the speciation of neo-endemics, as well as the persistence of relatively few paleo-endemics.

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Research Article Tue, 30 Jan 2024 10:00:00 +0200
Rediscovery and revalidation of the Brazilian endemic Vanilla schwackeana Hoehne (Orchidaceae): its distribution and phylogenetic position https://plecevo.eu/article/110331/ Plant Ecology and Evolution 157(1): 32-41

DOI: 10.5091/plecevo.110331

Authors: Emerson R. Pansarin

Abstract: Background and aims – With 40 species, Brazil is the centre of diversity for Vanilla. Frederico Carlos Hoehne described eight Vanilla species for the Brazilian flora, including Vanilla schwackeana, an obscure taxon currently assumed to be a synonym of V. planifolia. While studying Neotropical Vanilla, plants were found in gallery forests of the Vale do Rio Doce region, Minas Gerais, south-eastern Brazil. Based on the examination of the protologues of the Brazilian species, in addition to the study of herbarium specimens, it was verified that the plants correspond to the rare V. schwackeana. Material and methods – A redescription of V. schwackeana is provided, and a morphological comparison with other Neotropical taxa is presented. An illustration of V. schwackeana based on living specimens is provided, and its geographic distribution is presented based on recent findings. The position of V. schwackeana within Vanilla is discussed based on both morphological data and a molecular phylogeny. Key results – Vanilla schwackeana is distinguishable by its pseudopetiolate leaves, by its largely elliptic to obelliptic leaf blades with attenuate base and acuminate apex, by its apical racemes with small flowers, by its yellow labellum with white undulate-crenulate margins, and by its papillous appendages on the apical portion of the labellar crest. Both morphological and molecular data suggest a close relationship of V. schwackeana with V. appendiculata, V. hartii, and the Brazilian endemic V. rupicola. Based on current data, V. schwackeana is assessed as Critically Endangered. Conclusion – Integrative taxonomy was crucial to understand the identity and species boundaries of V. schwackeana. The V. appendiculata/V. schwackeana/(V. hartii/V. rupicola) clade comprises an unrecognized infrageneric Vanilla group. It seems plausible that the formation of a new infrageneric group will be necessary. As the habitat of V. schwackeana has been devastated by iron ore extraction, conservation strategies for this Brazilian endemic species will be necessary.

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Research Article Wed, 24 Jan 2024 10:30:00 +0200
Two new species of Hechtia (Bromeliaceae; Hechtioideae) from Jalisco, Mexico https://plecevo.eu/article/108472/ Plant Ecology and Evolution 157(1): 20-31

DOI: 10.5091/plecevo.108472

Authors: Alejandra Flores-Argüelles, Rodrigo Alejandro Hernández-Cárdenas, Santiago Rosales-Martínez, Adolfo Espejo-Serna, Ana Rosa López-Ferrari, Andrew Siekkinen

Abstract: Backgrounds and aims – The genus Hechtia (sensu lato) is distributed from the southern United States to northern Central America and includes 95 species. Recent botanical explorations, carried out in the Colima and Jalisco states in search of H. reticulata, led to the discovery of two new species. The aims of this work were to complete the morphological description of H. reticulata and describe these two new species. Material and methods – This study was based on fieldwork and on the revision of literature, protologues, type material, and herbarium specimens. The specimens collected were prepared for storage in the herbarium, analysed, measured, and descriptions were made; measurements were taken from dried specimens. Due to their morphological similarities and the closeness of their populations, the proposed species are compared with H. reticulata. Key results – We propose two new species of Hechtia for Mexico (H. costalegrensis and H. pacifica); an epitype and a complete description of H. reticulata are also provided. The diagnostic characters and morphological affinities of the new species are discussed, including complete morphological descriptions and images; a comparative table is presented, showing the morphological differences between the new species and H. reticulata. A distribution map of the taxa described here and of H. reticulata is included, as well as an identification key and a list of examined specimens of all Hechtia species known to date from Colima and Jalisco.

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Research Article Wed, 17 Jan 2024 09:08:00 +0200
Evolution of pollen grain morphology in Amorimia and allies evidences the importance of palynological apomorphies and homoplasies in Malpighiaceae systematics https://plecevo.eu/article/102524/ Plant Ecology and Evolution 156(3): 399-415

DOI: 10.5091/plecevo.102524

Authors: Carolina Prandi da Silva, Rafael Felipe de Almeida, Talita Kely Bellonzi, Eduardo Custódio Gasparino

Abstract: Background and aims – Pollen grain morphology is an important morphological character for aiding the systematics of flowering plants. For Malpighiaceae, only a single unpublished palynological study has comprehensively sampled ca 60 of this family’s 75 currently accepted genera. To test the systematic relevance of pollen morphology in Amorimia and allies, we characterised the pollen morphology of these lineages. We scored, coded, and mapped 12 characters onto the most recent molecular phylogeny of Amorimia and allies. Material and methods – We sampled 13 species of Amorimia as ingroup and two species of Mascagnia and Ectopopterys soejartoi as outgroup. Pollen grains were acetolised, characterised, and measured using light microscopy and scanning electron microscopy. Pollen quantitative measurements were submitted to a PCA multivariate analysis. Additionally, quantitative and qualitative characters were scored and coded into 12 characters and mapped onto the molecular phylogeny of Amorimia and allies. Key results – Amorimia and allies are stenopalynous due to all species showing the same pollen type, with some subtle differences between the pollen grains, such as details of ornamentation, shape, size, and thickness of the pollen exine. However, the patterns of pollen grain evolution showed that few qualitative and apomorphic characters are informative for intrageneric distinction (i.e. type and number of apertures), and almost all quantitative and homoplastic characters analysed were informative at infrageneric levels within Malpighiaceae. Conclusion – Our results demonstrate that even though the pollen morphology characters of Amorimia and allies show subtle variation, both qualitative and quantitative apomorphic and/or homoplastic characters are highly informative for intra- and infrageneric levels in Malpighiaceae when analysed in a phylogenetic context.

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Research Article Tue, 7 Nov 2023 09:30:00 +0200
A new purple-flowered Butia (Arecaceae) from the highlands of the Chapada dos Veadeiros (Brazil) https://plecevo.eu/article/110654/ Plant Ecology and Evolution 156(3): 383-398

DOI: 10.5091/plecevo.110654

Authors: Bruno Francisco Sant`Anna-Santos

Abstract: Background and aims – The highlands of the Chapada dos Veadeiros region comprise one of the largest savannah areas in central Brazil. The region includes large areas of the rare and little-known cerrado rupestre, which is home to numerous endemic species. During research on the Arecaceae flora of Chapada dos Veadeiros, a new species of Butia was discovered, and it is described here. Material and methods – The morphology and anatomy are described based on field collections. Following the default methodology, pinnae and flowers were analysed using LM (freehand cross- and longitudinal sections) and SEM. The new species is compared to its morphologically similar species from the Brazilian central plateau, and an identification key and distribution map were established. Key results – At first sight, the new species Butia soffiae resembles B. archeri, but with staminate and pistillate flowers, which are always purple, different in size, and congested in the rachillae. After close inspection, it is morphologically allied to B. buenopolensis, differing mainly by its glaucous peduncular bract – similar size to the inflorescence, herbaceous peduncle, numerous rachillae, purple floral colour, and inconspicuous staminodes. Differences in leaf anatomy, such as the presence of raphides, a cross-sectionally truncated midrib, and the number of accessory bundles on the midrib, also support the description of a new species. Two structures were recorded for the first time for the genus: squamiform trichomes at the base of the pistil and osmophores on the staminodes. The new species is assessed as Critically Endangered based on the restricted area of occurrence and anthropogenic threats. Conclusion – Butia soffiae is the first endemic Butia species described in Chapada dos Veadeiros. The type population is located near Chapada dos Veadeiros National Park, which is the subject of a bill that aims to reduce its area by 73%. The discovery of this new species reinforces the uniqueness of the local flora and the importance of maintaining the park.

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Research Article Mon, 23 Oct 2023 10:00:00 +0300
A new Ypsilopus (Orchidaceae, Angraecinae) from Zimbabwe and notes on the parallel evolution of extreme column exsertion in African angraecoids https://plecevo.eu/article/107313/ Plant Ecology and Evolution 156(3): 374-382

DOI: 10.5091/plecevo.107313

Authors: João Farminhão, Phillip J. Cribb

Abstract: Background and aims – A preliminary review of hawkmoth-pollinated angraecoids from Africa unveiled a remarkable case of parallel evolution of extreme column exsertion between the two species formerly classified in in the defunct genus Barombia. These belong to one clade of Aerangis, including A. gracillima and A. stelligera, and Ypsilopus sect. Barombiella, including Y. amaniensis and Y. schliebenii. The exploration of the geographical distribution of these two clades, followed by an examination of morphological variation within Y. sect. Barombiella, revealed that the disjunct population identified as Y. amaniensis from Zimbabwe represents an undescribed species. Material and methods – Occurrence records of Ypsilopus amaniensis, Y. schliebenii, Aerangis gracillima, and A. stelligera were comprehensively mapped and distribution patterns were visually analysed. Pollination syndromes and pollinaria attachment sites were inferred based on a review of floral and hawkmoth morphology. Standard herbarium practices and mining of photographs of wild and cultivated plants in social media allowed the description of the novelty. Key results – Ypsilopus zimbabweensis sp. nov. (Y. sect. Barombiella) is a narrow endemic of significant horticultural interest and it is preliminarily assessed as Endangered. The evolution of a Barombia-type column presents a parallel geographical pattern in the Aerangis gracillima–A. stelligera clade and Ypsilopus sect. Barombiella and probably induced a shift of pollen placement sites in these sphingophilous species.

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Research Article Thu, 19 Oct 2023 10:00:00 +0300
Novelties in the genus Acalypha (Euphorbiaceae, Acalyphoideae): two new species from northern Madagascar https://plecevo.eu/article/108024/ Plant Ecology and Evolution 156(3): 365-373

DOI: 10.5091/plecevo.108024

Authors: Iris Montero-Muñoz, Geoffrey A. Levin, Concepción Vaquero Lorenzo, Laura González, José M. Cardiel

Abstract: Background and aims – Taxonomic knowledge of Acalypha in the Western Indian Ocean Region (WIOR; including Madagascar, Comoros, Mascarenes, Seychelles, and the Scattered Islands) has increased greatly in the last few years. This paper is the latest in a series of publications that have contributed to create a robust taxonomic framework for Acalypha in this region. Material and methods – The descriptions and illustrations of the new species are based on herbarium specimens and on some field images. Descriptions were made following standard procedures. Maps was prepared using QGIS software and preliminary conservation assessments was made following IUCN guidelines and criteria. Key results – Two species of Acalypha from northern Madagascar are described as new to science: Acalypha bardotiana sp. nov., found on the Montagne des Français (Diana region), and Acalypha inaequibracteata sp. nov., found in the Binara forest (Sava region). Line drawings, field images, distribution maps, and a discussion of their morphological and phylogenetic affinities, as well as the preliminary conservation assessments are provided.

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Research Article Wed, 11 Oct 2023 09:30:00 +0300
Molecular phylogeny and character-mapping support the synonymy of Cordobia and Gallardoa in Mionandra (Malpighiaceae) https://plecevo.eu/article/101657/ Plant Ecology and Evolution 156(3): 352-364

DOI: 10.5091/plecevo.101657

Authors: Rafael F. de Almeida, Isa L. de Morais, Marco O.O. Pellegrini, Cassio van den Berg

Abstract: Background and aims – Cordobia, Gallardoa, Mionandra, and Peixotoa (Stigmaphylloid clade, Malpighiaceae) are four small, closely related genera comprising shrubs or lianas endemic to South American savannas, dry forests, and temperate steppes. Their generic limits have significantly changed in the last century, and past molecular phylogenetic studies of Malpighiaceae have not tested the morphological characters of this group to identify synapomorphies supporting these clades/genera. Material and methods – We sampled the monospecific Cordobia and Gallardoa, one species of Mionandra (out of 2 spp.), nine species of Peixotoa (out of 29 spp.), and a single species of Camarea and Janusia as outgroups. Bayesian and Maximum Likelihood analyses were carried out for this clade based on five molecular markers (i.e. ETS, ITS, PHYC, matK, and ndhF). A set of 16 macromorphological characters was scored and coded for identifying synapomorphies under the Maximum Likelihood criteria. Key results – Our molecular phylogeny recovered Peixotoa as monophyletic and sister to the clade comprising Cordobia + Gallardoa + Mionandra, strongly corroborating previous phylogenetic studies of Malpighiaceae. The character-mapping analyses recovered two synapomorphies supporting the Cordobia + Gallardoa + Mionandra + Peixotoa clade, six supporting Mionandra s.l. (i.e. Cordobia + Gallardoa + Mionandra), and five supporting Peixotoa. Cordobia and Gallardoa are proposed as synonyms of Mionandra, alongside the necessary combinations, typifications, and identification keys. Conclusions – Morphological characters related to the degree of connation of the stipules, leaf indumentum type, petiole length, inflorescence architecture, number of flowers per inflorescence, presence of a peduncle in the 1-flowered cincinni, sepal connation, posture and texture, petal width and margin integrity, staminode presence, shape and size, and the shape of the apex of styles were key in circumscribing these lineages. Mionandra s.l. is proposed and characterised, including a new combination, an identification key to distinguish its species, a distribution map, and taxonomy notes.

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Research Article Wed, 4 Oct 2023 11:00:00 +0300
Leaf traits of understory woody species in the Congo Basin forests changed over a 60-year period https://plecevo.eu/article/104593/ Plant Ecology and Evolution 156(3): 339-351

DOI: 10.5091/plecevo.104593

Authors: Yves Hatangi, Hippolyte Nshimba, Piet Stoffelen, Benoît Dhed’a, Jonas Depecker, Ludivine Lassois, Filip Vandelook

Abstract: Background and aims – While tropical forests play an important role in carbon sequestration, they are assumed to be sensitive to rising temperatures and prolonged drought. Plant functional traits are useful for understanding and predicting the effects of such changes in plant communities. Here, we analyse the variation of leaf traits of understory woody species of the Congo Basin rainforests over a 60-year period using herbaria as tools and we verify if this variation is potentially related to recent climate change. Material and methods – Leaves of five shrub species were collected in 2019–2022 in Congolese old-growth forests (Yangambi Biosphere Reserve, DR Congo) from different positions on the shrub. These leaves were compared with herbarium specimens collected in the same area before 1960. For both periods, we assessed leaf size, specific leaf area, stomatal size, and stomatal density for all species. Key results – The variability of the functional traits of the understory woody species are independent of the position of the leaves in the crown. This allows for the use of historic herbarium collections for trait analyses on tropical understory shrubs. The traits of the recently collected leaves were notably different from the traits of herbarium leaves collected in pre-1960: recent leaves were significantly larger, had a higher Specific Leaf Area, a smaller stomata pore length, and, apart from Coffea canephora, showed a lower stomatal density. Conclusion – The difference in traits over time is probably related to the increase in temperature and to atmospheric CO2 concentration, as the average temperature at Yangambi over the past 60 years has shown an upward trend consistent with global increasing CO2 levels, while the average annual rainfall has remained unchanged. Our results provide a first insight into the response of forest species to climate change in the Congo Basin forests, and on how the understory species and the ecosystem will react in the long term, when the temperature further increases.

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Research Article Fri, 29 Sep 2023 10:40:00 +0300
Vivipary, a rare phenomenon in Afrotropical Melastomataceae: first report in Amphiblemma ciliatum (Sonerileae) https://plecevo.eu/article/106696/ Plant Ecology and Evolution 156(3): 333-338

DOI: 10.5091/plecevo.106696

Authors: Marie Claire Veranso-Libalah, Chen Luo, Ehoarn Bidault

Abstract: Background and aims – Within angiosperms, vivipary has been reported in less than 0.1% of all species. We herein report the first occurrence of vivipary in an Afrotropical Melastomataceae and discuss its phylogenetic position, habit, habitat, and fruit attributes. Material and methods – Observational data were gathered from a field expedition to Gabon, and from herbarium specimens from BR, BRLU, P, and WAG. A phylogeny was generated to map all the eight species exhibiting vivipary in Melastomataceae. Key results – Amphiblemma ciliatum is currently the only known melastome species in the Afrotropics exhibiting vivipary. It is likely that its angular capsules depend on rainwater for seed dispersal. Conclusion – The combination of a herbaceous habit and angular fruits with the occurrence on shaded humid tropical rainforest floor during periods of incessant rainfall and high humidity might be responsible for vivipary in most Melastomataceae.

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Research Article Fri, 22 Sep 2023 11:00:00 +0300
Eulophia edwardii (Orchidaceae), a new species from the Pondoland Centre of Endemism in South Africa https://plecevo.eu/article/105931/ Plant Ecology and Evolution 156(3): 326-332

DOI: 10.5091/plecevo.105931

Authors: Benny Bytebier

Abstract: Background and aims – Despite the fact that the orchid flora of South Africa is well documented, new species are still being discovered. The identity of an Eulophia subpopulation from near Port Edward in KwaZulu-Natal has been ambiguous. Some thought that it belongs to Eulophia schnelliae, currently considered a synonym of Eulophia macowanii, whereas others were of the opinion that it was potentially a new species. Both hypotheses are investigated here. Material and methods – Plants were studied in the field and herbarium specimens, including types, were consulted. The relevant published literature was revised. Key results – Eulophia schnelliae is confirmed as a synonym of Eulophia macowanii. The Port Edward subpopulation does not match any known Eulophia taxon and is newly described as Eulophia edwardii, endemic to the Pondoland Centre of Endemism. It is only known from one subpopulation of about 200 individuals, which is threatened by urban development. It is, therefore, assessed as Critically Endangered according to Criterion B2ab(i,ii,iii). Conclusion – The newly described species increases the number of Eulophia species in South Africa to 29 and the number of endemic Eulophia species to 10. This discovery underlines the need for continued botanical inventories and protection of sensitive grasslands.

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Research Article Tue, 12 Sep 2023 13:13:00 +0300
The genera of Cyperaceae of Madagascar https://plecevo.eu/article/98847/ Plant Ecology and Evolution 156(3): 276-310

DOI: 10.5091/plecevo.98847

Authors: Fitiavana Rasaminirina, Isabel Larridon

Abstract: Background and aims – The rise of DNA sequencing in systematics has brought more understanding of the Cyperaceae family worldwide. Through these studies, it has been possible to delineate major clades and classify its species into subfamilies, tribes, and genera. Today, we have a good understanding of the species diversity and geographic distribution of the genera. However, in the case of Madagascar, the only complete taxonomic treatment of Cyperaceae dates from 1937. Although recent monographs exist for some genera in Madagascar, the taxonomic treatment of the Cyperaceae of Madagascar has not been updated until now. Hence, the present work aims to produce an updated treatment at the generic level including descriptions and an identification key of all Cyperaceae genera in Madagascar. Material and methods – Books and scientific articles containing descriptions of the genera of Cyperaceae of Madagascar, and information on their ecology and distribution were consulted, as well as herbarium specimens, collections, and data available from online herbaria and aggregator portals. Key results – Madagascar is very rich in Cyperaceae. The species of the Cyperaceae family on the island are distributed in 24 genera, including one endemic genus, i.e. Trichoschoenus. Ten genera are monotypic on the island. Sixteen of the 29 genera described in the Flore de Madagascar remain accepted but the others are now either synonyms of Cyperus, or no longer apply because they are absent from Madagascar, such as Scirpus. Regarding their habitat and ecology, some genera are specific to a particular habitat, like Costularia, while others that are very broadly distributed, like Cyperus and Scleria. Conclusion – Our study provides an updated overview of the genera of Cyperaceae of Madagascar, including an identification key, descriptions, and illustrations.

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Research Article Tue, 29 Aug 2023 11:16:00 +0300
The genus Malanea Aubl. (Rubiaceae) in the Atlantic Forest of Brazil https://plecevo.eu/article/103395/ Plant Ecology and Evolution 156(3): 257-275

DOI: 10.5091/plecevo.103395

Authors: Rafaela Sales Pereira Roxo, Maria Regina de Vasconcellos Barbosa

Abstract: Background and aims – Malanea (Rubiaceae) is a Neotropical genus of ca 40 species, 15 of which occur in Brazil, with nine found in the Atlantic Forest domain. This study aims to present a taxonomic treatment of the species occurring in the Atlantic Forest domain. Material and methods – We studied collections deposited in 15 Brazilian herbaria, ALCB, BHCB, BHZB, CEPEC, HUEFS, HUFU, IPA, JPB, MAC, OUPR, PEUFR, RFA, RB, UFP, and UFRN, and collections in NY were studied online. Specimens were identified using protologues and digital images of types available online. Key results – Of the nine species of Malanea previously recognized in the Atlantic Forest domain, we accepted seven, six of which are endemic. Malanea macrophylla has a wide distribution also occurring in other Brazilian phytogeographic domains, and adjacent countries. We expanded the distribution of four species and identified Bahia as the possible centre of diversity for the group in the domain. In addition, an identification key to the species, detailed descriptions, taxonomic notes, typifications, illustrations, maps of geographic distribution, and assessments of conservation status are provided. The names Malanea evenosa, M. forsteronioides, M. macrophylla, M. martiana, and M. spicata are here typified. The calculated conservation status revealed three Endangered species, two Vulnerable ones, M. forsteronioides as Near Threatened, and M. macrophylla with a status of Least Concern.

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Research Article Thu, 17 Aug 2023 15:00:00 +0300
To print in red ink: two new species of Hippeastrum (Amaryllidaceae) from the Brazilian Atlantic Forest https://plecevo.eu/article/95601/ Plant Ecology and Evolution 156(2): 239-256

DOI: 10.5091/plecevo.95601

Authors: Antonio Campos-Rocha, Alan William Meerow, Mauro Peixoto, Ingrid Koch, Patrícia Aparecida Messias, Julie Henriette Antoinette Dutilh

Abstract: Background and aims – The Atlantic Forest is among the five most important biodiversity hotspots in the world, harbouring one of the highest levels of endemism and species richness in the tropics. The region has been suggested as a centre of diversity for the genus Hippeastrum, which comprises about one hundred species distributed throughout the Neotropics. Due to its large and showy flowers, the genus is highly sought after by collectors and horticulturists around the world, with hundreds of hybrids produced and traded for centuries. However, most of its species are still known from only one or a few populations, and several are officially recognized as endangered. Monographic studies on the genus Hippeastrum in Brazil have revealed two likely microendemic new species from the Atlantic Forest. Material and methods – The morphological descriptions of the new species are based on herbarium specimens and cultivated plants, as well as in situ observations. Descriptions and measures were taken following standard procedures. Preliminary conservation assessments followed IUCN guidelines and criteria. Key results – Both species show typical morphology of the subgenus Hippeastrum, in which they should be placed. They can be distinguished from similar taxa, including some of the most widely distributed and known species of the genus, by several floral characters. Data on ecology, conservation, and photographs and illustrations are provided, as well as comparisons with related species. An identification key to the Brazilian Atlantic Forest species of Hippeastrum is provided, accompanied by photographs of these species in their natural habitats. Conclusion – The new species are considered critically endangered due to their single known location and small population size. The findings reinforce the need for continued sampling across different regions of the Atlantic Forest, as well as the importance of systematic studies conducted by specialist taxonomists.

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Research Article Thu, 6 Jul 2023 11:46:00 +0300
The family Zingiberaceae in Rwanda with description of two new species of Renealmia https://plecevo.eu/article/99146/ Plant Ecology and Evolution 156(2): 225-238

DOI: 10.5091/plecevo.99146

Authors: Eberhard Fischer, Dorothee Killmann, Jean-Baptiste M. M. Dhetchuvi

Abstract: Background and aims – The Zingiberaceae of Rwanda are revised, and three new records of Aframomum species (A. corrorima, A. daniellii, A. zambesiacum) are provided. One previously recorded species, A. alboviolaceum, has to be excluded from the Flora of Rwanda. Two new species of Renealmia are described from Rwanda and Burundi in connection with the preparation of the family treatment for the Flore d’Afrique centrale. Material and methods – Field work and standard herbarium practices were applied. Key results – Renealmia timmiorum sp. nov. is similar to R. cincinnata and R. cabrae, and R. susannae-katziae sp. nov. is similar to R. africana and R. dewevrei. The differences with these species are discussed and distribution maps for the new taxa are presented. Renealmia timmiorum is assessed as Least Concern (LC), while R. susannae-katziae is assessed as Endangered (EN).

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Research Article Thu, 8 Jun 2023 11:00:00 +0300
A new epilithic bromeliad (Stigmatodon, Tillandsioideae) from Pedra dos Três Pontões, Espírito Santo, Brazil, with an emended combination for the genus https://plecevo.eu/article/98904/ Plant Ecology and Evolution 156(2): 215-224

DOI: 10.5091/plecevo.98904

Authors: Dayvid Rodrigues Couto, André Pavioti Fontana, Andrea Ferreira da Costa, Claudio Nicoletti de Fraga

Abstract: Background and aims – Stigmatodon (Bromeliaceae) is a monophyletic genus currently comprising 33 species, all endemic to rocky outcrops, mainly inselbergs, from the Atlantic Forest and campos rupestres of the Espinhaço range, Brazil. Material and methods – Our fieldwork in the inselbergs of the Atlantic Forest of the state of Espírito Santo led to the discovery of a new Stigmatodon species with a tubo-laciniate stigma type. Standard herbarium taxonomy practices were adopted to study the novelty. Morphological data were obtained from herbarium specimens and fresh material collected in the field. Key results – Stigmatodon lemeanus is here described and illustrated. Diagnostic characters and affinities of the new species are discussed, accompanied by notes on its ecology, geographic distribution, and conservation status. A key to the species of Stigmatodon from Espírito Santo state is provided. The novelty is similar to S. goniorachis from coastal inselbergs of Rio de Janeiro and S. attenuatoides, another inselberg endemic from southern Espírito Santo. Stigmatodon lemeanus is preliminarily assessed as Vulnerable (VU) according to the IUCN Red List criteria. Additionally, we present a new combination of Tillandsia oligantha in Stigmatodon, correcting a nomenclatural error.

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Research Article Thu, 25 May 2023 18:16:00 +0300
The reproductive traits that contribute to the invasive success of Mediterranean onionweed (Asphodelus fistulosus) https://plecevo.eu/article/89362/ Plant Ecology and Evolution 156(2): 201-214

DOI: 10.5091/plecevo.89362

Authors: Oscar Sandino Guerrero-Eloisa, Jordan Golubov, María C. Mandujano, Pedro Luis Valverde

Abstract: Background and aims – Understanding the traits that lead to the invasion potential of invasive alien species (IAS) provides insight for their management. The reproductive traits of IAS help us understand the mechanisms that allow for their invasive potential, and colonization into new ranges. Asphodelus fistulosus is a native Mediterranean species commonly found invading Australia, South-East Asia, South Africa, and North America. Materials and methods – Two populations of A. fistulosus in the Chihuahuan Desert were monitored for reproductive phenology. Floral visitors and their behaviour were described, and we assessed the breeding system through floral morphological characters and the mating system in controlled pollination experiments. Key results – Reproductive phenology showed continuous reproduction throughout the year. Floral morphology suggested a facultative autogamous breeding system, but the mating system was mixed with autonomous selfing. Flowers lasted one day, with anthesis lasting 11 h. Floral visitors of A. fistulosus consisted of a variety of taxa including species of Coleoptera, Hymenoptera, and Lepidoptera, the exotic Apis mellifera being the most frequent visitor. Conclusions – The reproductive traits of A. fistulosus in the invaded range provide the biological potential for further invasion. The continuous production of reproductive structures attracts many diverse pollinators, and the autonomous self-pollination implies that a single plant has the potential to develop a new population, which makes the control of this IAS a global challenge.

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Research Article Fri, 12 May 2023 09:36:00 +0300
A taxonomic revision of the ecologically important Ochna holstii (Ochnaceae) complex using molecular and morphological data https://plecevo.eu/article/85589/ Plant Ecology and Evolution 156(2): 174-200

DOI: 10.5091/plecevo.85589

Authors: Toral Shah, Fandey H. Mashimba, Haji. O. Suleiman, Yahya S. Mbailwa, Vincent Savolainen, Isabel Larridon, Iain Darbyshire

Abstract: Background and aims – Ochna holstii and its allies represent an ecologically important group in a variety of lowland to montane habitats in tropical eastern and southern Africa. Identifying and delimiting species within this group has proved challenging due to a lack of variation in morphological characters. We combine genomic-scale data of multiple accessions per species with morphological data to generate a taxonomic revision for the Ochna holstii complex using a multi-evidence approach. Material and methods – A total of 50 samples representing eight species were analysed using target enrichment and a custom bait kit. Phylogenetic analysis was conducted using the multi-species coalescent model and a concatenation maximum likelihood method, and gene tree discordance was investigated. Herbarium specimens of the O. holstii complex were studied in detail for informative morphological characters, supplemented where possible from field collections, and a full taxonomic revision is provided. Key results – Within Ochna sect. Schizanthera Clade I, our study confirms that all species are monophyletic and supported by morphological data with the exception of O. holstii, which is paraphyletic. A new species, O. mchanga, previously confused with O. polyneura, is described, and the placement of another recently described species, O. maguirei, is confirmed for the first time using molecular data. Conclusion – The widespread montane tree Ochna holstii is non-monophyletic in its current circumscription and likely gave rise to the more range-restricted O. oxyphylla and O. stolzii. We suggest that an integrated taxonomy approach, using both molecular and morphological data, is essential for deciphering difficult species relationships in Ochna.

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Research Article Wed, 3 May 2023 11:00:00 +0300
A matter of warts: a taxonomic treatment for Drypetes verrucosa (Putranjivaceae, Malpighiales) and a new cauliflorous species from Cameroon and Nigeria, D. stevartii https://plecevo.eu/article/102004/ Plant Ecology and Evolution 156(2): 160-173

DOI: 10.5091/plecevo.102004

Authors: Alejandro Quintanar, Bonaventure Sonké, Murielle Simo-Droissart, Patricia Barberá, Moses Libalah, David J. Harris

Abstract: Background and aims – Specimens of a new tree species in the genus Drypetes (Putranjivaceae) distributed in Cameroon and eastern Nigeria, D. stevartii, were associated with D. verrucosa, another tree species endemic to Gabon, due to its warty fruits and to the overall morphological resemblances of both species. Material and methods – The present study is based on the study of 20 gatherings of D. verrucosa and 26 gatherings of D. stevartii. Morphological observations on herbarium specimens belonging to the new species and D. verrucosa were carried out in order to describe them. Key results – This treatment includes the detailed descriptions of these two species, the typification of their names, a comparative table summarizing their main morphological differences, an identification key, photographs of both, as well as information about their distribution, habitat, and phenology. Preliminary IUCN Red List assessments show that both D. verrucosa and D. stevartii are ‘Near Threatened’ species.

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Research Article Wed, 26 Apr 2023 09:30:00 +0300
Barking up the wrong tree: the dangers of taxonomic misidentification in molecular phylogenetic studies https://plecevo.eu/article/101135/ Plant Ecology and Evolution 156(2): 146-159

DOI: 10.5091/plecevo.101135

Authors: Rafael Felipe de Almeida, Marco O.O. Pellegrini, Isa L. de Morais, Rosangela Simão-Bianchini, Pantamith Rattanakrajang, Martin Cheek, Ana Rita G. Simões

Abstract: Background and aims – Keraunea is a Brazilian endemic genus that has sat uncomfortably in Convolvulaceae where it was placed due to an enlarged and adnate fruit bract typical of Neuropeltis. A recent molecular phylogeny suggested that two of its five morphologically almost identical species actually belong to two different families, Malpighiaceae (superrosids) and Ehretiaceae (superasterids). Later studies have demonstrated that Keraunea effectively belongs to Ehretiaceae, but the proposal of one species belonging to Malpighiaceae has remained problematic. In this study, we re-assess this hypothesis, discuss the issues that have led to this assumption, and offer insights on the importance of carefully using herbarium collections and incorporating morphological evidence in systematic studies. Material and methods – Sequences of matK, rbcL, and ITS for all 77 currently accepted genera of Malpighiaceae, K. brasiliensis and Elatinaceae (outgroup) were compiled from GenBank and analysed with Maximum Likelihood and Bayesian Inference criteria for nuclear, plastid and combined datasets. Additional database and herbarium studies were performed to locate and analyse all duplicates of the holotype of K. brasiliensis to check for misidentified or contaminated material. Key results – Our examination of expanded DNA datasets and herbarium sheets of all K. brasiliensis isotypes revealed that a mistake in tissue sampling was, in fact, what led to this species being proposed to belong in Malpighiaceae. Kew’s isotype had a leaf of Malpighiaceae (likely Mascagnia cordifolia) stored in the fragment capsule, which was sampled and sequenced instead of the actual leaves of K. brasiliensis. Recently published studies have settled the placement of Keraunea in Ehretiaceae (Boraginales) and proposed three additional species. Conclusions – DNA sequences can be helpful in classifying taxa when morphology is conflicting or of a doubtful interpretation, with molecular phylogenetic placement being established as a popular tool accelerating the discovery of systematic relationships. Nonetheless, molecular techniques are also susceptible to methodological mistakes, which necessitates building a solid foundation of plant morphology and taxonomy to avoid artefacts in phylogenetic studies.

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Research Article Wed, 19 Apr 2023 14:14:00 +0300
A new bluish-leaved Syagrus (Arecaceae) from an overlooked OCBIL in the Espinhaço Range (Brazil) https://plecevo.eu/article/101027/ Plant Ecology and Evolution 156(2): 129-145

DOI: 10.5091/plecevo.101027

Authors: Bruno Francisco Sant'Anna-Santos, Rafael Micheli, Luiz Fernando Lima Carvalho, Patrícia Soffiatti

Abstract: Background and aims – This study is part of ongoing research on the Arecaceae Flora of the Serra do Cabral, an isolated massif in the southwest of the Espinhaço Range in Minas Gerais State. Because of the isolation of the massif, the area has a rich biodiversity and a high level of endemism. While searching for populations of the rare and critically endangered Syagrus cabraliensis, a new bluish-leaved palm species was discovered and it is described here. Material and methods – The new species’ morphology is described based on field collections. The pinnae were analysed using SEM and LM cross- and longitudinal sections following default methodology. In addition, we compared the species to S. cabraliensis and provided ecological notes and a conservation status assessment. Key results – Syagrus carvalhoi resembles S. cabraliensis but they can easily be distinguished by morphoanatomical characters. Both species occur non-sympatrically in the Serra do Cabral, in contrasting microhabitats: S. carvalhoi in the southern quartzitic campos rupestres and S. cabraliensis in the northern ferruginous campos rupestres. A key to the known grass-like Syagrus species from the massif is provided. Based on the restricted area of occurrence and the anthropogenic threats, Syagrus carvalhoi is assessed as critically endangered. Conclusion – Syagrus carvalhoi is the second grass-like endemic Syagrus species from the Serra do Cabral and presents rare characters within the genus (grass-like aspect, colonial habit, flowers in tetrads, and the stem forking at or below the ground). This discovery corroborates that this isolated OCBIL is a home for endemic and rare palm species. The Serra do Cabral massif has proved a source of morphological and anatomical novelties in Arecaceae, affecting the taxonomy and understanding of the evolution and ecology of palms. Our results reinforce the notion that it is important to conserve this area with rich and rare biodiversity but under alarming and unprecedented threats.

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Research Article Wed, 12 Apr 2023 10:01:00 +0300
Reassessment of morphological species delimitations in the Cyperus margaritaceus-niveus complex using morphometrics https://plecevo.eu/article/97453/ Plant Ecology and Evolution 156(1): 112-127

DOI: 10.5091/plecevo.97453

Authors: Martin Xanthos, Simon J. Mayo, Isabel Larridon

Abstract: Background and aims – The Cyperus margaritaceus-niveus complex is a group of ten tropical species from sub-Saharan Africa and Madagascar: C. karlschumannii, C. kibweanus, C. ledermannii, C. margaritaceus, C. niveus, C. nduru, C. obtusiflorus, C. somaliensis, C. sphaerocephalus, and C. tisserantii. They are characterised by a capitate head of white-yellow spikelets and modified culm bases and recent molecular analysis puts them in a distinct clade. The group lacks a modern taxonomic revision, and the taxa described in the Flora treatments of the past 50 years differ considerably in their circumscription. In this study, morphometric analyses are used to test species limits to establish more stable morphological delimitations of the taxa. Material and methods – An examination of 15 morphological characters on 489 herbarium specimens was carried out and the data was analysed using Principal Component Analysis (PCA), Linear Discriminant Analysis (LDA) with cross-validation, and Classification and Regression Tree (CART) analysis. Cyperus kibweanus was not further considered due to lack of material. Key results – Both PCA and LDA showed varying degrees of overlap in the nine remaining taxa, with no single group clearly separating in multivariate space. However, cross-validation clearly showed C. margaritaceus as a distinct entity despite its overwhelming presence in the PCA. Both LDA and CART failed to separate C. niveus as a distinct group as its specimens were dispersed among the other groups. Differing results were obtained for other taxa depending on the type of analysis. Cyperus margaritaceus, C. nduru, and C. sphaerocephalus were divided into two groups by CART but re-examination of the specimens does not definitively support the idea that these infraspecific groups represent separate taxa. Conclusions – The results show that eight morphospecies are recognised by LDA and six morphospecies by CART. Characters used to separate the taxa in Flora treatments scored high loadings in the analysis showing their high taxonomic utility value. The methods used can be applied to resolving other complexes in the Cyperaceae.

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Research Article Wed, 22 Mar 2023 15:31:00 +0200
Sylvainia, a new monospecific genus within the subtribe Cephalanthinae (Rubiaceae, Naucleeae) https://plecevo.eu/article/90423/ Plant Ecology and Evolution 156(1): 85-111

DOI: 10.5091/plecevo.90423

Authors: María Florencia Romero, Ana Maria Gonzalez, Roberto Manuel Salas

Abstract: Background and aims – The genus Cephalanthus belongs to the tribe Naucleeae together with 26 other genera. Members of Cephalanthus mainly grow in temperate and subtropical wetlands in the Americas and Asia, but there is a single African species that is associated with forest margins and rocky outcrops in moist temperate grasslands. The genus comprises six species and was historically known to have species with a markedly disjunct distribution: three species are from the Americas: C. glabratus, C. occidentalis, and C. salicifolius; two species are from tropical Asia: C. angustifolius and C. tetrandrus, and one species is from tropical Africa: C. natalensis. Recent molecular phylogenetic studies have supported the monophyly of the genus, however, most of the morphological synapomorphies are absent in the only African species, which is sister to the remaining species of the genus. This work aims to provide a short taxonomic revision of the genus Cephalanthus, taking into consideration morphological aspects previously underestimated or not considered, and to describe a new monospecific genus based on comparative morphological analysis. Material and methods – Vegetative and reproductive material from all the species of Cephalanthus were analysed following conventional taxonomy techniques. Key results – We transferred C. natalensis to a new genus, Sylvainia. Morphological similarities and differences between Cephalanthus and the new genus are discussed. Cephalanthus glabrifolius, a poorly known species and previously considered a synonym of C. tetrandrus, is resurrected as a valid species, bringing the number of species in Cephalanthus to six again. All species are described, illustrated, and their known distributions plotted on regional maps. Conclusion – The subtribe Cephalanthinae now has two genera, its type Cephalanthus with six species, and a new monospecific genus Sylvainia endemic to south-eastern Africa. Based on the amended description of Cephalanthus, now absent from Africa, the generic concept is substantially modified, being represented now by three American and three Asian species.

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Research Article Wed, 15 Mar 2023 15:31:00 +0200
Novitates Gabonenses 93: a fresh look at Podostemaceae in Gabon following recent inventories, with a new combination for Ledermanniella nicolasii https://plecevo.eu/article/96359/ Plant Ecology and Evolution 156(1): 59-84

DOI: 10.5091/plecevo.96359

Authors: Ehoarn Bidault, Archange Boupoya, Davy U. Ikabanga, Igor Nguimbit, Nicolas Texier, Rolf Rutishauser, Attila Mesterházy, Tariq Stévart

Abstract: Background and aims – Podostemaceae is a family of strictly aquatic plants found in rapids and waterfalls. Despite a recent treatment in the Flore du Gabon, the family remained poorly known, with no major studies including Gabonese collections, and almost no targeted inventories since 1966. We present the first large-scale inventory of this family in Gabon, targeting Podostemaceae throughout the country, providing new additions to the flora of Gabon and many new records of poorly known species. Material and methods – Fieldwork was conducted in Gabon between 2017 and 2021. The collected specimens were primarily preserved in ethanol with associated silica gel-preserved material and photographs. Material available at BR, BRLU, LBV, MO, P, WAG, and Z/ZT was examined. For each species, information on distribution and ecology is presented, as well as a distribution map in Gabon. Key results – The 500 newly collected specimens represent 91.4% of all known collections of Podostemaceae from Gabon. Three taxa are newly recorded for the country, including one genus (Inversodicraea tenax, Ledermanniella schlechteri, and Saxicolella nana). New distribution records are also presented for 13 little-known species. Four taxa are excluded from the Gabonese flora (the genus Dicraeanthus, Inversodicraea ledermannii, Ledermanniella sanagaensis, and Macropodiella garrettii). To date, 20 species belonging to five different genera are known to occur in Gabon. A new combination is proposed for Ledermanniella nicolasii, and Inversodicraea tanzaniensis is now considered as a synonym of Inversodicraea tenax.

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Research Article Wed, 1 Mar 2023 11:31:00 +0200
Indications of an Achaea sp. caterpillar outbreak disrupting fruiting of an ectomycorrhizal tropical tree in Central African rainforest https://plecevo.eu/article/96572/ Plant Ecology and Evolution 156(1): 46-58

DOI: 10.5091/plecevo.96572

Authors: Julian M. Norghauer, David M. Newbery, Godlove A. Neba

Abstract: Background and aims – Where one or several tree species come to dominate patches of tropical forest, as many masting ectomycorrhizal legumes do in Central Africa, ecological theory predicts they may be prone to herbivory, which might alter their reproductive output. This was indirectly investigated in lowland rainforest in Cameroon for Tetraberlinia korupensis, whose crowns were attacked in 2008 by an outbreaking black caterpillar—identified as an Achaea sp., probably A. catocaloides—in Korup National Park. Material and methods – Field-collected data on tree-level seed and fruit (pod) production of T. korupensis in its 2008 masting event were compared with that of its two co-dominant neighbours (T. bifoliolata, Microberlinia bisulcata), whose populations masted in 2007 (and 2010). To do this, bivariate regression models (linear, polynomial, ZiG [zero-inflated gamma model]), contingency table analysis, and non-parametric measures of dispersion were used. Key results – Assuming T. korupensis is prone to Achaea caterpillar attacks, empirical data support the hypothesized lower proportion of adults participating in its masting (54% in 2008) than for either masting population of M. bisulcata (98% in 2007, 89% in 2010) or T. bifoliolata (96% in 2007, 78% in 2010). These fruiting T. korupensis trees were about one-third larger in stem diameter than conspecific non-fruiters and produced as many pods and seeds per capita as T. bifoliolata. However, regressions only modestly support the hypothesis that the positive tree size–fecundity relationship for T. korupensis was weaker (i.e. lower adj. R2) than for M. bisulcata (whose leaves are morphologically similar) or T. bifoliolata, with mostly similar dispersion about the median among these species. Conclusion – Altogether, the findings suggest a role for tolerance in nutrient-poor forests. It is postulated that instead of conferring resistance to herbivores, the ectomycorrhizas associated with these trees may enable them to more quickly recover from potential yet unpredictable insect outbreaks.

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Research Article Wed, 22 Feb 2023 11:42:00 +0200
The Italian endemic forest plants: an annotated inventory and synthesis of knowledge https://plecevo.eu/article/95929/ Plant Ecology and Evolution 156(1): 29-45

DOI: 10.5091/plecevo.95929

Authors: Federico Selvi, Giandiego Campetella, Roberto Canullo, Stefano Chelli, Gianniantonio Domina, Emmanuele Farris, Cristina Gasperini, Leonardo Rosati, Camilla Wellstein, Elisa Carrari

Abstract: Background and aims – Forests are among the most threatened ecosystems worldwide, and endemic plants are often a vulnerable component of the flora of a given territory. So far, however, understory forest endemics of southern Europe have received little attention and are poorly known for several aspects. Material and methods – We developed the first list of native vascular plants that are restricted to Italian forests. Available information on taxonomy, regional distribution, ecology, biology, functional traits, and conservation status was collected for each taxon, allowing to identify major knowledge gaps and calculate baseline statistics. Key results – The list includes 134 taxa, most of which are linked to closed-canopy forest habitats, while the others are also found in margins and gaps. The forest and non-forest Italian endemic flora differed in terms of taxonomic and life-form distribution. The rate and density of forest endemism increased with decreasing latitude and were highest in Sicily, Calabria, and Basilicata, where paleoendemic mono- or oligotypic genera also occur. Endemic phanerophytes were especially numerous on islands. Beech and deciduous oak forests were the most important habitats, but hygrophilous woodlands also host numerous endemics. Overall, the ecology, biology, and functional traits of the forest endemic taxa are still poorly known. The ratio diploids/polyploids was highest in the south and on the islands. Almost 24% of the taxa were assessed as “Critically Endangered”, “Endangered”, or “Vulnerable”, and 24% were categorized as “Data Deficient”, based on the IUCN system. Increasing frequency and intensity of fires was the most frequent threat. Conclusions – This work can contribute to implement the European forest plant species list and serve as a basis for further research on a unique biological heritage of the continent. However, more knowledge about these globally rare taxa is needed, to support their conservation in changing forest landscapes.

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Research Article Wed, 15 Feb 2023 11:31:00 +0200
Why fitness impacts of different herbivores may combine nonadditively, and why it matters to the ecology and evolution of plant-herbivore communities https://plecevo.eu/article/95982/ Plant Ecology and Evolution 156(1): 13-28

DOI: 10.5091/plecevo.95982

Authors: Michael J. Wise

Abstract: Background and aims – The manner by which the effects of multiple antagonists combine is a fundamental issue in ecology. This issue has been especially important in plant-herbivore evolutionary ecology—particularly predicting whether the combined fitness impacts of multiple herbivores on a shared host plant can be inferred by simply adding the individual impacts that each herbivore has when feeding alone. Despite accumulating empirical data, relatively little theoretical progress has been made in explaining why impacts of herbivore damage often combine nonadditively, as well as predicting the conditions that lead to a greater-than-additive (synergistic) or to a less-than-additive (subadditive) pattern. Material and methods – Based on considerations of limiting resources and source-sink relationships, I proposed and tested two hypotheses: 1) The fitness impacts of two species of herbivores that affect the same resource (i.e. feed on the same tissue in a similar fashion) will combine in a synergistic pattern (if that resource is not limiting reproduction when plants do not experience herbivory), and 2) The fitness impacts of two herbivores that affect different resources (i.e. feed on different tissues) will combine in a subadditive pattern. I performed a field experiment in which horsenettle (Solanum carolinense) was exposed to a factorial combination of four levels of leaf herbivory and five levels of simulated floral herbivory. Key results – The results were consistent with both hypotheses: 1) The combined fitness impact of flower damage that was simulated as being caused by two florivorous species feeding on the same plants was greater than the sum of the same total amount of damage when the two species were simulated as feeding individually; and 2) The combined fitness impact of the leaf and floral damage was less than the sum of the same total amount of damage when the two species fed individually. Conclusions – The main ecoevolutionary implication of these results is that subadditive impacts of leaf- and flower-feeding herbivores could weaken selection for resistance in horsenettle (or any plant species that hosts multiple herbivores), and thus subadditive impacts may contribute to the maintenance of diverse herbivore communities sharing a species of host plant.

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Research Article Wed, 8 Feb 2023 11:00:00 +0200
An assessment of Coutaportla (Chiococceae, Rubiaceae) with the description of a new species from Mexico https://plecevo.eu/article/89764/ Plant Ecology and Evolution 156(1): 3-12

DOI: 10.5091/plecevo.89764

Authors: Alejandro Torres-Montúfar, Hilda Flores-Olvera, Heriberto Ávila-González, Arturo Castro-Castro, Helga Ochoterena

Abstract: Background and aims – Ongoing studies on Mexican Rubiaceae revealed an undescribed species of Coutaportla endemic to the Sierra Madre Occidental pine-oak forests in the state of Sinaloa, near the border with Durango, Mexico. The species is here described and illustrated, and its morphological characters are compared with those of the other species in the genus. Material and methods – This study is based on field observations, examination of herbarium specimens including digital images, and morphological studies based on samples from dried and spirit specimens. Key results – The morphological comparison of taxonomically important characters among the species of Coutaportla reveals conditions that were previously not reported for the genus. The placentation and ovule number of C. lorenceana, which belongs in the Portlandia complex, is comparable to that in the Chiococceae tribe. This tribe was proposed to include the latter complex based on molecular data, but the classification was controversial according to the morphology. Coutaportla lorenceana hence provides a morphological link between the Portlandia complex and the taxa traditionally placed in Chiococceae. The new species is assessed as Critically Endangered following the IUCN Red List criteria.

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Research Article Mon, 9 Jan 2023 09:15:00 +0200
A new species of Parianella (Poaceae, Bambusoideae, Olyreae) marks the southernmost distribution of the genus in Brazil https://plecevo.eu/article/95130/ Plant Ecology and Evolution 155(3): 425-432

DOI: 10.5091/plecevo.95130

Authors: Fabrício Moreira Ferreira, Reyjane P. Oliveira, Lynn G. Clark, Cassiano A. Dorneles Welker

Abstract: Background and aims – Parianella is a relatively recently described genus of the subtribe Parianinae (Poaceae, Bambusoideae, Olyreae) that includes two species, and it is supposedly endemic to the Bahian Coastal Forests in the central region of Atlantic Forest, Brazil. Herein, we describe and illustrate a new species of the genus, comparing it with the other species of Parianella. We also provide an updated distribution map of the genus and the conservation status of the new taxon. Material and methods – This study was based on the analysis of herbarium specimens and a literature review. The conservation assessment is based on field observations and spatial analyses, following IUCN guidelines and criteria. Key results – During a review of the Poaceae collection of the MBML Herbarium, two Parianinae specimens with interesting features were found. A detailed morphological analysis revealed that these specimens belong to a new species of Parianella. The new taxon was collected in two localities in the southern portion of the Brazilian state of Espírito Santo, one in the municipality of Santa Leopoldina and the other in the Duas Bocas Biological Reserve, municipality of Cariacica. Both localities are situated in the Krenák-Waitaká Forests, one of the three subregions of the central Atlantic Forest region, and an area of great floristic diversity, including bamboo species. Conclusion – Parianella capixaba represents the southernmost distribution of the genus known to date. With the description of this new species, the total number of bamboos in Espírito Santo state rises to 52 species in 18 genera.

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Research Article Wed, 14 Dec 2022 10:00:00 +0200
A striking new species of Rhipidocladum (Poaceae: Bambusoideae: Bambuseae: Arthrostylidiinae) with single, terminal-spikelet synflorescences, endemic to Jalisco, Mexico https://plecevo.eu/article/86519/ Plant Ecology and Evolution 155(3): 417-424

DOI: 10.5091/plecevo.86519

Authors: Eduardo Ruiz-Sanchez, Christopher D. Tyrrell, Pablo Carrillo-Reyes, A. T. Nuño-Rubio

Abstract: Background and aims – Rhipidocladum, a woody bamboo genus distributed from Mexico to Argentina, has raceme like synflorescences of multiple spikelets. Six of the 21 known species occur in Mexico. In this study, we present a full description, distribution map, illustrations, and photographs of an unusual new Rhipidocladum species endemic to Jalisco, Mexico. Additionally, we provide an updated key to the species of Rhipidocladum in Mexico. Material and methods – This study was based on fieldwork, literature, and herbarium specimens review. Specimens collected were analysed and photographed during fieldwork. The conservation assessment is based on spatial analyses, following the IUCN guidelines and criteria. Results – This is the first species in the genus Rhipidocladum that has synflorescences with only a single, terminal spikelet. Rhipidocladum singuliflorum occurs only in three localities in the municipality of Puerto Vallarta, Jalisco, Mexico. This species inhabits the canyon slopes of rivers in subdeciduous and tropical dry forests, at 6–150 m a.s.l. According to our IUCN assessment, this new species should be considered Critically Endangered.

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Research Article Wed, 30 Nov 2022 11:32:00 +0200
Species delimitation and phylogenetic relationships of Silene villosa s.l. (Caryophyllaceae, sect. Silene s.l.) using nrDNA ITS and cpDNA rps16 https://plecevo.eu/article/85790/ Plant Ecology and Evolution 155(3): 394-403

DOI: 10.5091/plecevo.85790

Authors: Farzaneh Jafari, Maryam Keshavarzi, Richard K. Rabeler

Abstract: Background and aims – Species delimitation is a necessary investigation for widely distributed species. Examination of herbarium specimens and descriptions in local floras revealed that two forms of Silene villosa were recognized. Form B of S. villosa has been identified as a separate species named S. wendelboi. However, the latter species was not treated as a separate species in local floras. By using molecular tools, we investigated if these forms of S. villosa should be treated as two distinct species or be retained in S. villosa. Material and methods – We created two datasets containing 84 and 46 accessions of nrDNA ITS and cpDNA rps16 regions, respectively, which were extracted mainly from GenBank. Phylogenies were reconstructed using Maximum Likelihood and Bayesian analyses. Key results – We propose that S. villosa and S. wendelboi are two separate species, morphologically and phylogenetically. Silene wendelboi was first recognized in SW Iran but we show that the species is distributed in the Persian Gulf and the E Mediterranean region as well. In most cases, S. wendelboi is erroneously identified as S. villosa in these regions. The distribution of S. villosa is much wider, also occurring in SW Asia and North Africa, Egypt, and Algeria. Silene wendelboi differs from S. villosa in calyx texture, calyx length, the ratio of calyx length to pedicel, the shape of the apex of the coronal scale, seed morphology, and molecular data, i.e. ITS and rps16 sequences. Based on those two markers, S. villosa is closely related to S. ayachica, while S. wendelboi shows affinity to S. arabica.

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Research Article Thu, 3 Nov 2022 11:30:00 +0200
Floral ontogeny links Dialypetalanthus (Condamineeae) with the floral developmental morphology of other Rubiaceae https://plecevo.eu/article/84606/ Plant Ecology and Evolution 155(3): 379-393

DOI: 10.5091/plecevo.84606

Authors: Alexander Vrijdaghs, Petra De Block, Karen L. G. De Toni, Erik Smets, Elmar Robbrecht

Abstract: Background – Vegetative and fruit characters of the Amazonian genus Dialypetalanthus point to a position in Rubiaceae. However, its floral morphology is so deviant that the genus was often placed in a family of its own. Even relationships outside Gentianales were postulated. Current molecular phylogenetic studies firmly show that Dialypetalanthus belongs to Rubiaceae. Aims – This study aims to understand the idiosyncratic floral morphology in Dialypetalanthus and to compare it with the floral development in two other Condamineeae genera as well as in other Rubiaceae for which ontogenetic data are available. Material and methods – SEM and LM based floral ontogeny in Dialypetalanthus fuscescens, Mussaendopsis beccariana, and Pogonopus exsertus. Results and main conclusions – Flowers in Dialypetalanthus develop a stamen-corolla-calyx tube, which can be considered as a floral morphological link between the genus and the other Rubiaceae. The polyandrous androecium originates from an annular intercalary meristem at the adaxial side of the stamen-corolla-calyx tube.

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Research Article Wed, 19 Oct 2022 10:57:00 +0300
Waltheria marielleae (Byttnerioideae, Malvaceae), a new species from north-eastern Brazil supported by morphological and phylogenetic evidence https://plecevo.eu/article/94921/ Plant Ecology and Evolution 155(3): 353-362

DOI: 10.5091/plecevo.94921

Authors: Thales Silva Coutinho, Mariela Analía Sader, Andrea Pedrosa-Harand, Marccus Alves

Abstract: Background – Waltheria marielleae is a new species of Malvaceae endemic to north-eastern Brazil that occurs only in the states of Pernambuco and Alagoas, in areas of Atlantic Forest and Caatinga. It is characterized by cinereous leaves, axillary and sessile to subsessile inflorescences, pallid yellow corollas with apically eciliate petals and fan-plumose stigmas. Material and methods – DNA was extracted from leaf tissue and the markers matK, ndhF, and ITS were amplified using universal primers, with PCR products purified and sequenced. Phylogenetic analysis was performed, including DNA sequences obtained from GenBank. Morphological studies were based on the analysis of specimens deposited in seven herbaria and specimens collected in Pernambuco state, Brazil. Results – Waltheria marielleae is morphologically and phylogenetically related to pantropical W. indica and W. ackermanniana, with these three species forming a well-supported clade. Overall, phylogenetic molecular analysis suggests the monophyly of Waltheria, with the two currently proposed sections also being monophyletic, and Melochia as its sister group. The new species is assessed here as Endangered, according to IUCN criteria. In addition, we formally present new occurrences of W. ackermanniana and W. rotundifolia. Conclusion – In this study, a complete morphological description, illustration, distribution map, and phylogenetic tree are provided for Waltheria marielleae. This species is compared with morphologically and phylogenetically related species (W. ackermanniana, W. indica, and W. rotundifolia) and an identification key to the species occurring in Alagoas and Pernambuco is provided.

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Research Article Wed, 21 Sep 2022 10:54:00 +0300
Increasing knowledge on the diversity of canelas-de-ema in the campo rupestre: two new species of Vellozia (Velloziaceae) from the southern Espinhaço Range, Brazil https://plecevo.eu/article/94326/ Plant Ecology and Evolution 155(3): 343-352

DOI: 10.5091/plecevo.94326

Authors: Andressa Cabral, Renato Albuquerque Magri, Jenifer de Carvalho Lopes

Abstract: Background and aims – Two new species of Vellozia (Velloziaceae) are here described and illustrated, Vellozia albohexandra and V. mellosilvae. These new species are morphologically similar to Vellozia armata, V. luteola, and V. inselbergae, probably belonging to the same informal group. Material and methods – Morphological and anatomical descriptions were based on herbarium specimens and in situ observations. Standard taxonomy and plant anatomy practices and methods were applied. Key results – Vellozia albohexandra can be easily distinguished from the other species of the group of V. luteola by its sessile flowers with white and smaller petals and sepals, six stamens, and smaller style and stigma. The species is endemic to the Cristália municipality, Minas Gerais state, and has been classified as Data Deficient according to IUCN criteria. Vellozia mellosilvae shares morphological affinities with V. armata, but it is distinguished by the leaves with serrate margin and abaxial furrows, longer and evident pedicel, and larger petals and sepals. This species is endemic to the Itacambira municipality, and should be considered Critically Endangered.

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Research Article Wed, 7 Sep 2022 16:31:52 +0300
A new species of Amorphophallus (Araceae) from Eastern D.R. Congo, and a new record of the genus from Rwanda https://plecevo.eu/article/93804/ Plant Ecology and Evolution 155(3): 333-342

DOI: 10.5091/plecevo.93804

Authors: Eberhard Fischer, Bonny Dumbo, Landry Dumbo

Abstract: Background and aims – A new species of Amorphophallus (Araceae) is described from D.R. Congo in connection with preparing the family treatment for the Flore d’Afrique centrale. Another species is recorded for the first time from Rwanda. Methods – Standard herbarium practices were applied. Key results – Amorphophallus dumboi sp. nov. is related to A. margretae. The differences between these species are discussed and distribution maps for the taxa are presented. Both species are range-restricted in the Albertine Rift and preliminarily assessed as Critically Endangered. Amorphophallus mayoi is for the first time recorded for Rwanda. The taxon, originally described as a subspecies of A. calabaricus, is raised here to specific rank.

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Research Article Fri, 26 Aug 2022 08:08:48 +0300
Nuclear ribosomal phylogeny of Brachystegia: new markers for new insights about rain forests and Miombo woodlands evolution https://plecevo.eu/article/91373/ Plant Ecology and Evolution 155(2): 301-314

DOI: 10.5091/plecevo.91373

Authors: Arthur F. Boom, Jérémy Migliore, Esra Kaymak, Pierre Meerts, Olivier J. Hardy

Abstract: Background and aims – Brachystegia is a species-rich tree genus found in tropical Africa and a typical element of Miombo woodlands, a widely distributed subtype of the Zambezian savanna. Plastid DNA was shown to be largely uninformative to assess species phylogenetic relationships due to widespread chloroplast capture among species. Here, we aim to assess the capacity of nuclear ribosomal DNA (rDNA) to clarify the phylogeny of Brachystegia species while accounting for intra-individual site polymorphisms (2ISPs), which are often present in rDNA and potentially phylogenetically informative. Material and methods – Genome skimming sequencing on 47 samples representing 27 of the 29 currently recognized Brachystegia species, allowed us to retrieve complete nuclear ribosomal cistrons encoding for 18S, 5.8S, and 25S rRNA genes (35S rDNA). We reconstructed the Brachystegia phylogeny using Maximum Likelihood methods based on the standard substitution model or integrating 2ISPs (GENOTYPE implementation in RAxML-NG). We additionally tested the effect of partitioning the data (one partition for rDNA genes and one for the ITS1+ITS2). We also conducted network inferences (Neighbor-Net splits graph), as a strict bifurcative approach might not properly model topological uncertainty at shallow phylogenetic depth. Key results – 2ISPs-aware and standard phylogenetic reconstructions are largely congruent. We identified several well-supported main clades clarifying the species relationships, including two clades of Miombo woodlands species. Miombo Group A includes species with ovoid to globose axillary dormant buds, while Miombo Group B species have flattened ones. Two morphologically close Brachystegia species (B. kennedyi and B. leonensis) found in Guineo-Congolian rain forests form also a robustly supported clade. 2ISPs coding allowed to identify an additional Guineo-Congolian clade (B. eurycoma and B. nigerica). Ribosomal DNA therefore proves more useful to explore the generic phylogeny than plastid DNA but the species relationships within and among the main clades remain poorly resolved, probably due to recent diversification and/or recurrent hybridization, so that the diversification of Brachystegia remains to be more properly characterised. Conclusion – Nuclear and plastid phylogenetic reconstructions of Brachystegia species are discordant. Even if not well-resolved, rDNA phylograms and networks are characterized by taxonomic sorting, while we observe a strictly geographic sorting in the plastid dataset. Most of the species’ relationships remain to be characterized using additional nuclear markers combined with in-depth morphological investigations.

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Research Article Fri, 12 Aug 2022 12:01:31 +0300
Revision of Carapichea (Rubiaceae-Psychotrieae) in the Guianas, with two new combinations and transfer of three species to Notopleura https://plecevo.eu/article/90936/ Plant Ecology and Evolution 155(2): 275-300

DOI: 10.5091/plecevo.90936

Authors: Olivier Lachenaud, Piero G. Delprete

Abstract: Background and aims – The genus Carapichea (Rubiaceae), recently resurrected and separated from Psychotria, currently includes 24 Neotropical species and is morphologically heterogeneous. A revision of the genus in the Guianas is presented here, as part of the authors’ work on the Rubiaceae treatment in the Flora of the Guianas series. Material and methods – This paper is based on a study of herbarium specimens from BBS, BM, BR, BRB, CAY, INPA, K, P, P-JJR, and U; type specimens from other herbaria were consulted online. Some of the species were also studied in the field by the authors. Normal practices of herbarium taxonomy have been applied. Results – Three species previously included in Carapichea (C. altsonii, C. nivea, and C. sandwithiana) show aberrant characters for the genus and are transferred to Notopleura; new combinations are published for the former two (N. altsonii and N. nivea). Eight species of Carapichea, one of them still imperfectly known, are recorded from the Guianas; a ninth species, C. araguariensis, is included in this revision as it is expected to occur in the region. New combinations are published for two species: Carapichea galbaoensis and C. squamelligera, based on Psychotria galbaoensis and P. squamelligera, respectively; the former species was previously included in synonymy of C. guianensis, which is here redefined in a narrower sense. The delimitation of C. ligularis is expanded to include C. pacimonica as a synonym. The first records of C. adinantha in French Guiana – and the Guiana Shield – are documented. The taxonomy of the two remaining species, C. tillettii and C. urniformis, is left unchanged. For every species a complete description is presented, as well as data on distribution, ecology, phenology, local names (when known), and a list of collections studied.

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Research Article Tue, 2 Aug 2022 16:16:18 +0300
The fate of Holoregmia, a monospecific genus endemic to the Brazilian Caatinga, under different future climate scenarios https://plecevo.eu/article/90511/ Plant Ecology and Evolution 155(2): 261-274

DOI: 10.5091/plecevo.90511

Authors: Taynara Rabelo-Costa, Paulo Weslem Portal Gomes, Brenda Oliveira Rocha, Iury Leite Cruz, Ravena Santiago Alves, Tiê Rocha de Sousa Oliveira, José Luís Passos Cordeiro, Moabe Ferreira Fernandes, Eimear Nic Lughadha, Marcelo Freire Moro

Abstract: Background and aims – Climatic fluctuations during the Pleistocene altered the distribution of many species and even entire biomes, allowing some species to increase their range while others underwent reductions. Recent and ongoing anthropogenic climate change is altering climatic patterns very rapidly and is likely to impact species’ distributions over shorter timescales than previous natural fluctuations. Therefore, we aimed to understand how Pleistocene and Holocene climatic fluctuations might have shaped the current distribution of Holoregmia and explore its expected distribution under future climate scenarios. Material and methods – We modelled the potential distribution of Holoregmia viscida (Martyniaceae), a monospecific plant genus endemic to the semi-arid Caatinga Domain in Brazil. We used an ensemble approach to model suitable areas for Holoregmia under present conditions, Paleoclimatic scenarios, and global warming scenarios in 2050 and 2090. Key results – Holocene climates in most Caatinga were too humid for Holoregmia, which restricted its suitable areas to the southern Caatinga, similar to its current distribution. However, under global warming scenarios, the Caatinga is expected to become too dry for this lineage, resulting in a steady decline in the area suitable for Holoregmia and even its possible extinction under the most pessimistic scenario modelled. Conclusion – The predicted extinction of the ancient and highly specialized Holoregmia viscida highlights the possible consequences of climate change for some species of endemic Caatinga flora. Invaluable phylogenetic diversity may be lost in the coming decades, representing millions of years of unique evolutionary history and consequent loss of evolutionary potential to adapt to future environmental changes in semi-arid environments.

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Research Article Fri, 22 Jul 2022 10:20:53 +0300
Impatiens smetsiana, another example of convergent evolution of flower morphology in Impatiens https://plecevo.eu/article/89701/ Plant Ecology and Evolution 155(2): 248-260

DOI: 10.5091/plecevo.89701

Authors: Steven B. Janssens, Hermann Taedoumg, Steven Dessein

Abstract: Background and aims – The genus Impatiens is known for its enormous convergent phenotypic adaptation, with similar floral traits having independently evolved in distantly related lineages. The large functional convergence of Impatiens flowers causes a high degree of homoplasy for several phenotypic characters resulting in increased difficulties to distinguish between species with a similar morphology that are only distantly related, however. As a result, some species remain under the radar, as they are confused with other well-known species. This was the case for a new Impatiens species from the Tchabal Mbabo Mountains in Cameroon – Impatiens smetsiana – that was initially mistaken for the morphologically similar species I. erecticornis, an endemic from Central East Africa. Material and methods – A combined molecular-morphological approach was applied in which phylogenetics (ITS, ImpDEF1, and ImpDEF2), biogeography, and age estimation analyses were combined with morphological data on floral and vegetative structures. Key results – In this study, we demonstrate the close affinity of the newly collected material with a group of Equatorial West African species, including I. filicornu, I. nzabiana, I. oumina, and I. kamerunensis. The present finding represents a clear case of convergent evolution in which two distantly related taxa independently converged on practically the same flower morphology. Conclusion – Within Impatiens, several examples of floral homoplasy have been observed yet not in such a clear way. The convergent evolution of the flowers of I. smetsiana and I. erecticornis is undoubtedly closely correlated with an adaptation to a similar pollination syndrome.

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Research Article Wed, 6 Jul 2022 11:01:20 +0300
Medicinal Vitex species (Lamiaceae) occupy different niches in Haut-Katanga tropical dry woodlands https://plecevo.eu/article/89394/ Plant Ecology and Evolution 155(2): 236-247

DOI: 10.5091/plecevo.89394

Authors: Salvatora Nsenga Nkulu, Pierre Meerts, Edouard Ilunga wa Ilunga, Mylor Ngoy Shutcha, David Bauman

Abstract: Background and aims – Sustainable management of the medicinal plant resources provided by tropical forests is of utmost importance to human populations in developing countries. Trees and shrubs of the genus Vitex (Lamiaceae) are of great medicinal importance in Haut-Katanga (SE D.R. Congo), frequently used to treat tropical diseases. However, the security of supply is threatened, particularly by urban sprawl and mining. A conservation strategy for medicinal plants is urgently needed. In this context, we try to better understand the ecological factors (mostly soil) explaining the distribution of three medicinal species of Vitex (Lamiaceae) (V. fischeri, V. madiensis, and V. mombassae) that co-occur in the tropical dry woodlands in the region of Lubumbashi. Material and methods – In 114 plots (10 m radius), comprising at least one species of Vitex, all woody species with a DBH ≥ 10 cm were inventoried and soil samples were collected. Multivariate Regression Trees (MRT) combined with indicator species index IndVal and Redundancy analysis (RDA) were used to characterise habitats and woody plant communities associated to each Vitex species and to explain the variability of plant community composition. Key results – Four habitats were identified, and the three Vitex species differ significantly in ecological range. Vitex fischeri is a specialist of a most distinctive community on high Mg and low Al soil (termite mounds). Vitex mombassae is indicative of one habitat, corresponding to low altitude (< 1230 m) plots. Vitex madiensis has a broader range, being a generalist of all habitats except termite mounds. Conclusion – These results emphasise the importance of a detailed knowledge of species ecology to design species-specific conservation strategies, even for congeneric species occurring in sympatry in the same landscape.

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Research Article Wed, 29 Jun 2022 12:01:18 +0300
The breeding system of Hyacinthoides non-scripta (Asparagaceae): assessing the role of geitonogamy with captive pollinators https://plecevo.eu/article/85658/ Plant Ecology and Evolution 155(2): 182-188

DOI: 10.5091/plecevo.85658

Authors: Javier Guitián, Pablo Guitián

Abstract: Background and aims – In self-incompatible species, geitonogamous pollen deposition can result in stigma clogging, with negative effects on cross-fertilisation and subsequently reduced fruit and seed set. In this work, using laboratory and field experiments with pollinators in captivity, we describe the reproductive system of Hyacinthoides non-scripta and analyse the effect of the different mechanisms of pollen transfer, trying to quantify the effect of geitonogamy on the reproductive success of the species. Material and methods – Using laboratory and field experiments with pollinators in captivity we evaluated the effect of the different types of pollen transfer. Key results – The results show that H. non-scripta is a self-incompatible species and the pollen tubes in autogamous and geitonogamous pollination are rejected at the base of the style. In the field experiments, the presence of geitonogamous pollen on the stigma did not prevent subsequent fertilization by xenogamous pollen, but it reduced seed production. Conclusion – This study provides evidence that natural rates of geitonogamy significantly reduce female fitness in plants with large numbers of flowers per inflorescence and show how experiments with captive pollinators can help quantify the intensity of this effect.

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Research Article Thu, 28 Apr 2022 20:00:00 +0300
Mitracarpus semirianus (Spermacoceae, Rubiaceae), an overlooked new species from the “campo rupestre” of Bahia, northeastern Brazil, with notes on Mitracarpus lhotzkyanus https://plecevo.eu/article/84548/ Plant Ecology and Evolution 155(1): 165-177

DOI: 10.5091/plecevo.84548

Authors: João Carmo, André Scatigna, Gustavo Shimizu, André Simões

Abstract: Background and aims – Mitracarpus semirianus, an overlooked new species from the “campo rupestre” of the Chapada Diamantina, in the state of Bahia, northeastern Brazil, is here described and illustrated. Specimens of the new species have been previously identified as M. frigidus or M. lhotzkyanus, with which its distinction is discussed. We also provide an updated description of the latter, with notes on its type specimens. In addition, we comment on the distribution, habitat, and preliminary conservation status of both M. semirianus and M. lhotzkyanus. We also provide an updated identification key to the species of Mitracarpus occurring in Brazil.Material and methods – This study was based on fieldwork collections and observations and analysis of specimens deposited in herbaria. Preliminary conservation status assessments follow the IUCN Red List criteria.Key results – Mitracarpus semirianus differs from M. frigidus and M. lhotzkyanus by its glabrous stems, winged at each angle, wing margin hirsute, glabrous leaf blades, and the oblongoid and slightly compressed seeds, with a smooth longitudinal groove dorsally and an inverted “Y”-shaped groove ventrally. The new species is assessed as Endangered according to the IUCN criteria. Furthermore, it is more likely that Riedel, not Lhotzky, collected the original material of the name M. lhotzkyanus. This species is glabrate, not completely glabrous, presenting a generally strigose indumentum on the stems, stipular sheaths, and leaf blades.

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Research Article Wed, 30 Mar 2022 16:30:00 +0300
New and little-known species of Englerodendron (Leguminosae-Detarioideae) from Central Africa, with a revised key to the genus https://plecevo.eu/article/84547/ Plant Ecology and Evolution 155(1): 153-164

DOI: 10.5091/plecevo.84547

Authors: Olivier Lachenaud, Ehoarn Bidault

Abstract: Background and aims – The genus Englerodendron (Leguminosae-Detarioideae) has recently been enlarged to include Isomacrolobium and Pseudomacrolobium, and currently includes 18 tropical African species. The recent discovery of a new species in Gabon has led us to re-evaluate the delimitation of several taxa in the genus.Material and methods – This paper is based on field work by the authors in Gabon, and on a study of herbarium material from BR, BRLU, K, LBV, MO, P, and WAG; normal practices of herbarium taxonomy have been applied.Results – Englerodendron nguemae is described and illustrated as a new species, endemic to Gabon. It is remarkable for the variation in its leaves, which may be 2-jugate, 1-jugate, or unifoliolate on the same plant. The species is most similar to E. brachyrhachis, but the latter has uniformly 2-jugate leaves; E. nguemae also differs in its longer and more broadly winged leaf rachis (if present) that is convex (not flat) above, its stamen filaments pubescent at the base, and its glabrous style. Several collections from the Democratic Republic of the Congo, previously associated with E. obanense, are considered here to represent two different taxa. One of them, E. macranthum (a new combination and name at new rank based on Macrolobium isopetalum var. macranthum, which is raised to species status), is endemic to the Mayombe range and differs from E. obanense by its inflorescences branched from the base or nearly so, and its shorter 1-seeded pods. The other taxon, still imperfectly known and here treated as Englerodendron sp. A, is endemic to the Kivu region; it differs from E. obanense by its large foliaceous stipules and from E. conchyliophorum by the lack of a basal auricle on the stipules. In addition, the first records of E. leptorrhachis from Equatorial Guinea, and of E. conchyliophorum from the Republic of the Congo, are documented, and a revised key to the now 21 species (one undescribed) of Englerodendron is presented.

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Research Article Wed, 30 Mar 2022 16:30:00 +0300
Seed morphology of Hamelieae with emphasis on the Deppea complex (Cinchonoideae, Rubiaceae) https://plecevo.eu/article/84486/ Plant Ecology and Evolution 155(1): 51-69

DOI: 10.5091/plecevo.84486

Authors: María Aguilar-Morales, Helga Ochoterena-Booth, Teresa Terrazas

Abstract: Background and aims – The neotropical tribe Hamelieae currently includes 16 genera mainly characterized by raphides, ebracteolate inflorescences, and 4-merous flowers with contorted corolla aestivation. Within this tribe, the circumscription of Deppea has been particularly controversial, as depending on the authors, several morphologically closely related genera are either treated as synonyms or accepted as such. This generic group, hereafter referred to as the Deppea complex, consists of up to 10 genera. Within Rubiaceae, seed morphology has proved to have taxonomic value for generic circumscriptions, however, it remained unexplored for Hamelieae and the Deppea complex.Material and methods – We present a detailed study of the seed morphology of 37 species representing 15 out of the 16 genera recognized within Hamelieae, including all putative genera of the Deppea complex. Using scanning electron and light microscopy, we investigate 16 quantitative and qualitative seed characters that could have taxonomic value.Key results – Our results show that the combination of some seed characters, such as shape and colour, dorsiventral compression, hilum position, and the periclinal microrelief, helps to distinguish some genera and most species, supporting or refuting the current taxonomic circumscription.Conclusion – We conclude that the seed morphology within Hamelieae has taxonomic value but should be combined with other characters to achieve unequivocal delineation of the genera.

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Research Article Wed, 30 Mar 2022 16:30:00 +0300
Monophyly and transoceanic dispersal in the widespread floating club-rush clade, Isolepis subgenus Fluitantes (Cyperaceae) https://plecevo.eu/article/84466/ Plant Ecology and Evolution 155(1): 41-50

DOI: 10.5091/plecevo.84466

Authors: Jan-Adriaan Viljoen, Terry Hedderson, Charlotte Sletten Bjorå, Muthama Muasya

Abstract: Background and aims – Numerous lineages in the Western Cape of South Africa show affinities with the floras of tropical Africa and Australasia. Isolepis subgenus Fluitantes, comprising seven to nine species, includes the broadly-defined I. fluitans, which occurs throughout Africa into Europe and Asia, as well as on both sides of the Indian Ocean. Thus, it is well suited for testing the generality of both the Cape-to-Cairo pattern of dispersal and transoceanic dispersal between southern Africa and Australasia.Material and methods – We inferred a dated population-level phylogeny based on new sequence data from the nuclear ITS and the chloroplast atpI–H gene regions. We constructed dispersal–extinction–cladogenesis models in Lagrange to infer ancestral areas and to compare the likelihoods of stepping-stone and long-distance modes of dispersal.Key results – The Fluitantes originated in the Cape about 7 million years ago (mya). They spread stepwise onto the mountains of East Africa and thence into Europe and the islands of the Indian Ocean, seemingly tracking their ancestral habitat. Australasia was colonised by a single long-distance dispersal event ca 3 mya. Incongruence between the plastid and nuclear gene trees was apparent for the Australasian taxa, I. crassiuscula, I. lenticularis, and I. producta, with their atpI–H sequences placing them with I. ludwigii in the Fluitantes and the ITS nrDNA resolving them in the Proliferae. Furthermore, two African taxa (I. graminoides, I. inyangensis) diagnosed on unique morphology are resolved as part of the widespread I. fluitans.Conclusion – This study supports and extends the northward migration model that accounts for the Cape element of the Afromontane flora. Australasia was colonised directly from southern Africa, perhaps assisted by wind or waterfowl. Despite ancient hybridization associated with dispersal, we recognise the three taxa in Australasia as distinct, but synonymise I. graminoides and I. inyangensis into the widespread I. fluitans.

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Research Article Wed, 30 Mar 2022 16:30:00 +0300
Morphometric analysis provides evidence for two traditionally defined species of the Tillandsia erubescens complex (Bromeliaceae) https://plecevo.eu/article/84524/ Plant Ecology and Evolution 155(1): 29-40

DOI: 10.5091/plecevo.84524

Authors: Ana L. Martínez-García, Claudia T. Hornung-Leoni, Irene Goyenechea Mayer Goyenechea, Julian Bueno-Villegas, Carolina Granados Mendoza

Abstract: Background and aims – A linear morphometric analysis of three taxa of the Tillandsia erubescens complex, composed of T. erubescens var. arroyoensis, T. erubescens var. erubescens, and T. erubescens var. patentibracteata, is presented to evaluate their circumscription. Additionally, their taxonomic rank as varieties or species is discussed considering the obtained results. Geographic distribution, the influence of climate, elevation, and geographic distance on morphological differences between the taxonomic entities is explored.Material and methods – Of a total of 110 herbarium specimens reviewed, 44 were measured. These were previously identified as T. erubescens var. arroyoensis, T. erubescens var. erubescens, or T. erubescens var. patentibracteata. Factor and cluster analyses were performed using 16 quantitative morphological characters. The resulting groups were considered as taxonomic entities supported by morphometric characters, and species distributions were plotted against Mexican biogeographic provinces. A single Mantel test was performed to evaluate the correlation between morphology and climatic variables, elevation, and geographic distance.Key results – The specimens referred to as T. erubescens var. arroyoensis were separated morphometrically from the other two varieties. The most important characters to differentiate T. erubescens var. arroyoensis from T. erubescens var. erubescens were total size, width and length of the leaf sheath and leaf blade, and the number of flowers. The non-overlapping geographical distribution of T. erubescens var. arroyoensis and T. erubescens var. erubescens supports their recognition as independent taxonomic entities. Our study did not support the separation between T. erubescens var. erubescens and T. erubescens var. patentibracteata, which is also reflected by their overlapping geographic distributions. Both precipitation and geographic distance were correlated with the morphological differences among the species.Conclusion – Our morphometric and geographical distribution study supports the recognition of T. arroyoensis and T. erubescens as different species, while no evidence was found to maintain T. erubescens var. erubescens and T. erubescens var. patentibracteata as different taxonomic entities. We provide a set of morphological characters that can be used to distinguish between T. arroyoensis and T. erubescens, including the leaf sheath and leaf blade width, and the number of flowers. Morphological characters agree with the geographic distribution of the studied taxa.

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Research Article Wed, 30 Mar 2022 16:30:00 +0300
Taxonomic description and pollination ecology of Cyrtorchis okuensis (Orchidaceae, Angraecinae), a new species endemic to the Cameroon Volcanic Line https://plecevo.eu/article/24710/ Plant Ecology and Evolution 154(3): 483-496

DOI: 10.5091/plecevo.2021.1823

Authors: Laura Azandi, Tariq Stévart, Bonaventure Sonké, Murielle Simo-Droissart, Tania D’haijère, Vincent Droissart

Abstract: Background and aims – A recent taxonomic and molecular study of the genus Cyrtorchis revealed three new species. Here, we describe one of these new species, endemic to the Cameroon Volcanic Line (CVL), and compare it to its closest relatives. Its conservation status is provided along with detailed information on its ecology and reproductive biology.Material and methods – A detailed examination of 21 herbarium specimens was performed using standard practices of herbarium taxonomy. The conservation status of the new species was assessed using the IUCN Red List Categories and Criteria. Furthermore, we investigated the reproductive biology of the new species in an easily accessible subpopulation in Cameroon and tested the hypothesis of hawkmoth pollination in the genus Cyrtorchis. Key results – The newly discovered species, here named C. okuensis, is restricted to the montane forest (1600 to 2500 m elevation) of the CVL and is currently assessed as Near Threatened (NT). Among angraecoid orchids in which hawkmoth pollination is recorded (~16 species), C. okuensis has the shortest nectar spur (19–40 mm). In situ observations revealed hawkmoths with short proboscis of the genus Hippotion (H. celerio, H. eson, and H. osiris) as the main pollinators. The rate of pollination and fruiting under natural conditions was low and among the 448 surveyed flowers only 38.8% (174/448 flowers) had their pollinia removed, 19% produced fruits (87/448 flowers), and 16% (70/448 flowers) set mature fruits. Conclusion – Cyrtorchis okuensis is clearly differentiated from C. submontana by its longer and wider floral bracts, longer anther caps, and wider triangular dorsal sepal.

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Research Article Tue, 23 Nov 2021 00:00:00 +0200
Phylogeny of the Neotropical element of the Randia clade (Gardenieae, Rubiaceae, Gentianales) https://plecevo.eu/article/24707/ Plant Ecology and Evolution 154(3): 458-469

DOI: 10.5091/plecevo.2021.1889

Authors: Rodrigo Borges, Sylvain Razafimandimbison, Nádia Roque, Catarina Rydin

Abstract: Background and aims – Generic limits of the tropical tribe Gardenieae (Ixoroideae, Rubiaceae) have partly remained unsettled. We produced a new phylogeny of the Randia clade, with emphasis on its Neotropical clade comprising five genera (Casasia, Randia, Rosenbergiodendron, Sphinctanthus, and Tocoyena). The result was subsequently used to evaluate and discuss: a) the respective monophyly of the above-mentioned genera and their interrelationships; b) relationships within Tocoyena and the evolutionary relevance of its subgeneric classification; and c) the monophyly of the morphologically variable T. formosa.Material and methods – We examined the phylogeny of the Randia clade based on maximum likelihood and Bayesian analyses of sequence data from two nuclear (ETS and Xdh) and two plastid (petB-petD and trnT-F) DNA regions from 59 individuals (including seven representatives from the remaining Ixoroideae).Key results – The Neotropical clade of the Randia clade comprises three major lineages, the Randia armata subclade, the Randia-Casasia subclade and the Rosenbergiodendron subclade. Neither Casasia nor Randia is monophyletic. Tocoyena is sister to Rosenbergiodendron + Sphinctanthus and is subdivided into three lineages: the Tocoyena pittieri group, the Tocoyena guianensis group, and the core Tocoyena. Tocoyena williamsii is paraphyletic with respect to T. pittieri. Tocoyena formosa is polyphyletic and should be re-circumscribed.Conclusions – Our results demonstrate the monophyly of each of the relatively species-poor genera Rosenbergiodendron, Sphinctanthus, and Tocoyena, and confirm their close affinity. The serial classification of Tocoyena does not reflect the evolutionary history of the genus. The paraphyly of T. williamsii with respect to T. pittieri, together with their morphological similarities and geographic distributions, support the inclusion of the former in the latter. Our study calls for additional phylogenetic work on Casasia and the more species-rich genus Randia. While the respective monophyly of both genera is rejected here, future work with a broader representation of Randia is needed.

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Research Article Tue, 23 Nov 2021 00:00:00 +0200
Checklist of vascular plants for Wind River Indian Reservation (USA) high-elevation basins: ecological drivers of community assemblages https://plecevo.eu/article/24620/ Plant Ecology and Evolution 153(2): 292-311

DOI: 10.5091/plecevo.2020.1682

Authors: Colleen Friday, John Scasta

Abstract: Background and aims – Native American reservations in the United States provide biodiversity critical for conservation and ecosystem functions. Unfortunately, botanical inventories are less common for reservations than other land jurisdictions. Such ecological importance and needs are apparent for the Wind River Indian Reservation (WRIR), the 7th largest reservation in the US (>890,000 ha) that is shared by the Eastern Shoshone and Northern Arapaho.Material and methods – A botanical study for two WRIR high-elevation basins (Saint Lawrence Basin (SLB) and Paradise Basin (PB)) to (1) reconcile a 1960 plant list, and (2) quantify plant communities ecologically was conducted. In 2017, 106 monitoring sites were established to quantify species presence. Across basins, 231 total vascular plant taxa (221 to species and 10 to genus) were identified, or > 3× more plant species than noted in the 1960 list. In SLB, 222 plant taxa (213 to species and 9 to genus) were identified and in PB 98 plant taxa (90 to species and 8 to genus) were identified. In 2018, sites were re-sampled to quantify species abundance, soil pH, organic matter, soil nutrients, CEC, salts, and texture. Key results – Slope and elevation explained species distributions in the topography ordination and soil organic matter, pH, texture, P, and K explained species distributions in the soil ordination. Eleven exotic species, and one rare endemic species were documented with implications for empowering tribal management. Using a classification approach followed by an indicator species analysis and fidelity (Phi) assessment, we identified 14 unique plant communities and related these to 6 alliances and 7 associations across 6 macrogroups from the US National Vegetation Classification database. These indicator species of communities included sedges (Carex aquatilus), grasses (Pseudoroegneria spicata, Elymus elymoides, Achnatherum lettermanii, Elymus trachycaulus subsp. trachycaulus, Poa glauca subsp. rupicola), forbs (Polygonum bistortoides, Balsamorhiza incana, Castilleja flava), shrubs (Artemisia tridentata, Betula glandulosa, Dasiphora fruticosa subsp. floribunda) and trees (Pinus contorta).Conclusion – The plant taxa, plant communities, and ecological drivers documented in this study will enhance tribal and federal monitoring of these high-elevation WRIR basins.

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Checklist Wed, 8 Jul 2020 00:00:00 +0300
A new and endemic species of Drosera (Droseraceae) from Madagascar https://plecevo.eu/article/24619/ Plant Ecology and Evolution 153(2): 283-291

DOI: 10.5091/plecevo.2020.1705

Authors: Andreas S. Fleischmann, Nivo Rakotoarivelo, Aymeric Roccia, Paulo Gonella, Lala Roger Andriamiarisoa, Aina Razanatsima, Fortunat Rakotoarivony

Abstract: Background and aims – This study is part of an ongoing revision of the world Drosera species. During herbarium revisions of Drosera from Madagascar, a new species was identified and is here described.Methods – The species’ morphology is described based on herbarium studies and observation of living plants in situ, and ecological notes from field observations are provided. The species is compared and contextualized within the current subgeneric classification of Drosera.Key results – The new species, Drosera arachnoides, is recognized as most closely related to another Malagasy-endemic, D. humbertii, from which it is morphologically and ecologically distinct. The new species is placed within D. subg. Drosera sect. Ptycnostigma. Based on the restricted occurrence, the species is assessed as Vulnerable, following IUCN categories and criteria. A key to the Drosera species from Madagascar is provided.Conclusion – Drosera arachnoides is the second endemic Drosera species in Madagascar and raises the total number of species on the island to six.

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Regular Paper Wed, 8 Jul 2020 00:00:00 +0300
The hyperdominant tropical tree Eschweilera coriacea (Lecythidaceae) shows higher genetic heterogeneity than sympatric Eschweilera species in French Guiana https://plecevo.eu/article/24500/ Plant Ecology and Evolution 153(1): 67-81

DOI: 10.5091/plecevo.2020.1565

Authors: Myriam Heuertz, Henri Caron, Caroline Scotti-Saintagne, Pascal Pétronelli, Julien Engel, Niklas Tysklind, Sana Miloudi, Fernanda Gaiotto, Jérôme Chave, Jean-François Molino, Daniel Sabatier, João Loureiro, Katharina Budde

Abstract: Background and aims – The evolutionary history of Amazonia’s hyperabundant tropical tree species, also known as “hyperdominant” species, remains poorly investigated. We assessed whether the hyperdominant Eschweilera coriacea (DC.) S.A.Mori (Lecythidaceae) represents a single genetically cohesive species, and how its genetic constitution relates to other species from the same clade with which it occurs sympatrically in French Guiana.Methods – We sampled 152 individuals in nine forest sites in French Guiana, representing 11 species of the genus Eschweilera all belonging to the Parvifolia clade, with emphasis on E. coriacea. Samples were genotyped at four simple sequence repeat (SSR) markers. We delimited gene pools, i.e., genetically coherent putative taxa, using STRUCTURE software and principal component analysis. We compared the genetic assignment of individuals with their morphological species determination and estimated genetic diversity and differentiation for gene pools and species. We also estimated genome size using flow cytometry.Key results – SSR profiles commonly displayed up to four alleles per genotype, suggesting that the investigated Eschweilera species bear a paleopolyploid signature. Flow cytometry suggested that the studied species are diploid with haploid genome sizes of 871–1046 Mbp. We detected five gene pools and observed a good correspondence between morphological and genetic delimitation for Eschweilera sagotiana Miers and the undescribed morphospecies E. sp. 3 (which resembles E. grandiflora (Aubl.) Sandwith), and to a lesser extent for E. decolorans Sandwith and E. micrantha (O.Berg) Miers. Eschweilera coriacea was the most genetically diverse species and included individuals assigned to each gene pool. Conclusions – We found no conclusive evidence for cryptic species within E. coriacea in French Guiana. SSRs detected fewer gene pools than expected based on morphology in the Parvifolia clade but discriminated evolutionary relationships better than available plastid markers. A positive trend between demographic abundance of species and allelic richness illustrates that hyperdominants may have a high evolutionary potential. This hypothesis can be tested using more powerful genomic data in combination with tree phenotypic trait variation and characterization of niche breadth, to enhance our understanding of the causes of hyperdominance in Amazonian trees.

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Regular Paper Thu, 26 Mar 2020 00:00:00 +0200
Assessment of plant species diversity associated with the carob tree (Ceratonia siliqua, Fabaceae) at the Mediterranean scale https://plecevo.eu/article/24537/ Plant Ecology and Evolution 151(2): 185-193

DOI: 10.5091/plecevo.2018.1423

Authors: Alex Baumel, Pascal Mirleau, Juan Viruel, Magda Bou Dagher Kharrat, Stefano La Malfa, Lahcen Ouahmane, Katia Diadema, Marwa Moakhar, Hervé Sanguin, Frédéric Médail

Abstract: Background and aims – The thermophilous woodlands of the Mediterranean region constitute reservoirs of genetic resources for several fruit trees. Among them, the carob tree (Ceratonia siliqua) is a key component of traditional Mediterranean agroecosystems but its ecology was never assessed at the scale of its whole distribution area. Fortunately, phytosociological literature shelters invaluable resources for several issues in conservation, among them the possibility to analyse plant biodiversity at regional or continental scale. Here, we present the results of a comprehensive survey of the phytosociological literature associated to carob tree. Methods – We collected 1542 floristic relevés performed in 18 geographical areas distributed around the Mediterranean in which the presence of C. siliqua was recorded. Species composition of the plant communities was analysed by multivariate ordination and hierarchical classification, and species diversity was evaluated by rarefaction and prediction analyses of Hill numbers. Key results – Multivariate analyses revealed that plant communities associated with the carob tree are well differentiated between the Western and Eastern basins. A wider range of floristic differentiation is revealed in the Western basin where the vegetation reaches its maximal heterogeneity. By comparison, in the Eastern basin the plant assemblages associated with the carob tree are more homogeneous and with a lower species richness but a higher Simpson diversity. Conclusions – The large ecological range of the Mediterranean carob trees is potentially an important evolutionary legacy for the conservation of genetic resources and seed sourcing for new uses such as restoration ecology.

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Regular Paper Wed, 22 Aug 2018 00:00:00 +0300